Grubač families are mainly Croats and they are mostly from Jastrebarsko area , also Serbs, very rarely Montenegrins. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Middle Bosnia (Skender Vakuf area). In Imljani in Middle Bosnia every ninth inhabitant had the family name Grubač.
Prevalence
About 210 people with faimily name Grubač live in Croatia today, in 100 households. There were 290 of them in the middle of the past century, and their number decreased by 30 percent. They are located in the most of Croatian counties, in 33 cities and 31 other places, mostly in Zagreb (35), Sibenik (15), Siveric (10), Nasice (<10), and in Brodjani (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over ten times, the first time 1917 in source List of Dignitaries, Officials and Public Servants of the Kingdom of Croatia-Slavonia.